One of the leading causes of spine-related pain is the rupture or degeneration of discs located between lumbar vertebrae (xe2x80x9clumbar intervertebral discsxe2x80x9d). Pain in the lower extremities may be caused by compression of spinal nerve roots by such damaged discs, while low back pain may be caused by collapse of these discs and by the adverse effects of bearing weight through a damaged, unstable vertebral joint. One conventional method of managing this problem is to treat the problematic intervertebral disc with energy.
In some instances, the disc is globally heated. U.S. Pat. No. 5,433,739 (xe2x80x9cSluitjer Ixe2x80x9d) proposes inserting an RF electrode or other heating electrode into the intervertebral disc and globally heating the entire intervertebral disc to a temperature significantly above body temperature. See col. 2, lines 52-56. Sluijter I teaches that this process can denervate the neural structures within the disc on a global or semi-global basis, thus relieving the patient of back pain related to stress of the disc and its surface. See col. 5, line 65-col. 6, line 2. Sluijter I further notes that the precise anatomical mechanism of this pain relieving process has not been totally clarified, and discloses not only that anatomical material changes within the disc material itself and the resulting volumetric changes may play some role, but also that the spread of heat to large neural structures in the proximity of the disc may be additional contributory factors of significance. See col. 13, lines 28-37.
In some instances, only the nucleus of the disc is treated. For example, Choy et al., Spine, 17:8 (1992), pp. 949-956, discloses using a laser to evaporate the nucleus pulposus. It is believed that evaporation of the nucleus reduces the pressure within the disc, thereby relieving the pressure upon the nerves therein.
In some instance, only the inner wall of the annulus fibrosus portion of the disc is heated. U.S. Pat. No. 6,261,311 (xe2x80x9cSharkeyxe2x80x9d) proposes using a floppy wand-like probe for fully contacting and resistively heating a portion of the inner wall of the annulus fibrosus to a temperature of about 45-70xc2x0 C. It is believed that heating the inner wall in this manner may coagulate and/or denervate the collagenous annular wall leading to increased stability of the vertebral joint and/or eliminating the ability of the annular wall to sense pain.
U.S. Pat. No. 6,105,581 (xe2x80x9cEggersxe2x80x9d) discloses a radiofrequency (xe2x80x9cRFxe2x80x9d) probe which uses an electrically conductive fluid to help ablate tissue within the spine. Eggers discloses coating portions of the probe with an electrically insulative coating to produce xe2x80x9cnon-active portions of the probe which help the surgeon selectively ablate tissuexe2x80x9d. See col. 4, line 60 to col. 5, line 10. FIG. 15b of Eggers discloses a transverse cross-section view of a loop electrode wherein active portions of electrode 194 lie in essentially the same plane. Eggers further recites selected spinal applications for this device, including laminectomy/discectomy procedures for treating herniated discs, decompressive laminectomy for stenosis in the lumbosacral and cervical spine, posterior lumbrosacral and cervial spine fusions, treatment of scoliois associated with vertebral disease, foraminotomies to remove the roof of on the intervertebral foramina to relieve nerve root compression and anteror cervical and lumbar discectomies. None of these applications involve the therapeutic treatment of an intervertebral disc which results in an essentially intact disc.
In some instances, the nucleus pulposus is subjected to two power levels of RF energy. For example, U.S. Published patent application No. 2001/0029370 discloses a method of treatment whereby a single probe ablates a portion of the nucleus pulposus as it advances through the nucleus pulposus, and then heats the nucleus pulposus (using bipolar RF energy) as it is withdrawn from the nucleus pulposus in order to coagulate the collagen within the nucleus pulposus.
Some investigators have proposed using ultrasound technology as a means for heating the intervertebral disc. For example, U.S. Pat. No. 5,571,147 (xe2x80x9cSluijter IIxe2x80x9d) proposes using an ultrasound probe to heat the intervertebral disc
U.S. Pat. No. 5,620,479 (xe2x80x9cDiedrich Ixe2x80x9d) discloses an ultrasound applicator for thermal therapy of tumors and benign tissues using heat generated from acoustic energy, which includes a segmented array of individually controllable tubular ultrasound transducers through which an inner probe extends. See col. 3, lines 6-10. The segmented array disclosed by Diedrich I in FIG. 1 is a linear array of ultrasound sources along the longitudinal axis of the probe. Typically, ultrasound probes are configured to emit ultrasound waves in a fill 360xc2x0 radius about the axis of the probe. Diedrich I also proposes masking a portion of the radius so that ultrasound is emitted through only a portion of the probe circumference.
U.S. Pat. No. 5,391,197 (xe2x80x9cBurdettexe2x80x9d) proposes radially segmenting the ultra sound transducers (as in FIG. 23a) in order to adjust the power distribution in the angular expanse (see col. 10, line 17).
Some investigators have focused upon nerves contained within the vertebral bodies which are adjacent the problematic disc. For example, PCT Patent Publication No. WO 01/0157655 (xe2x80x9cHeggenessxe2x80x9d) discloses ablating nerves contained within the vertebral body by first boring into the vertebral body with a probe, and then ablating the nerves therein with the probe. Heggeness discloses using laser devices, electricity transmitting devices, fluid transmitting devices and thermal devices, and devices for carrying either chemotherapeutic or radioactive substances as candidate ablation devices.
EPO Patent Published Patent Application No. EP 1 059067 A1 (xe2x80x9cCosmanxe2x80x9d) discloses ablative treatment of metastatic bone tumors, including those within the spine. Pain relief is reportedly achieved by penetrating the bone wall with a suitable probe, and applying heat through the probe to ablate either the bone tumor or the tissue near the bone tumor. Cosman also teaches that the treatment may also be used to ablate the nerves and nerve ramifications in and/or around the bone to desensitize them against further tumor encroachment. See col. 11, lines 7-11.
In general, the prior art methods for treating back pain appear to focus upon identifying a single problematic tissue and treating only that tissue with energy. In addition, the prior art does not disclose or appreciate any need for treating back pain by treating two different tissue sites (e.g., both the intervertebral disc and the adjacent vertebral body portions of the adjacent vertebrae) within the same therapeutic procedure. In addition, the prior art does not disclose or appreciate any need for probes which are adapted for therapeutically treating different tissue sites associated with back pain.
The present inventors have recognized that back pain may be generated within an individual patient from a multitude of different tissue sites. For example, back pain within a single patient may be generated not only by nerves within that patient""s vertebrae, but also by nerves with that patient""s intervertebral discs. Simply, there may not be just a single tissue site responsible for a patient""s back pain. Accordingly, in one aspect of the present invention, there is provided a method of treating back pain wherein at least two separate tissue sites (e.g., both the intervertebral disc and at least one adjacent vertebra) are therapeutically treated within the same procedure, preferably with a single probe.
In particular, in accordance with the present invention, there is provided a device for therapeutically treating back pain, comprising:
a) a probe having a proximal portion and a distal portion,
b) first and second treatment sources, each source located in the distal portion of the probe,
wherein the first treatment source is adapted to therapeutically treat a first tissue site, the second treatment source is adapted to therapeutically treat a second different tissue site, and
wherein the first and second different tissue sites are selected from the group consisting of:
i) a first intervertebral disc,
ii) a first vertebra,
iii) a first spinal ligament, and
iv) a first spinal facet joint capsule,
v) a second intervertebral disc,
vi) a second vertebra,
vii) a second spinal ligament, and
viii) a second spinal facet joint capsule.
Also in accordance with the present invention, there is provided a method of treating back pain, comprising the step of therapeutically treating first and second different tissue sites with a single device, each tissue site being selected from the group consisting of:
i) a first intervertebral disc,
ii) a first vertebra,
iii) a first spinal ligament,
iv) a first spinal facet joint capsule,
v) a second intervertebral disc,
vi) a second vertebra,
vii) a second spinal ligament, and
viii) a second spinal facet joint capsule.
In addition, the inventors have recognized that back pain may be generated within an individual patient from a multitude of different components within a single spinal tissue site. For example, back pain within a single patient may be generated not only by the nerves within the annulus fibrosus of that patient""s intervertebral disc, but also by the nucleus pulposus with that patient""s same intervertebral disc. Simply, there may not be just a single component within a tissue site which is responsible for a patient""s back pain. Accordingly, in one aspect of the present invention, there is provided a method of treating back pain wherein at least two separate components of the same tissue site (e.g., both the annulus fibrosus and the nucleus pulposus within the same intervertebral disc) are therapeutically treated within the same procedure, preferably with a single probe.
In particular, in accordance with the present invention, there is provided a device for therapeutically treating back pain, comprising:
a) a probe having a proximal portion and a distal portion,
b) first and second treatment sources adapted to therapeutically treat an intervertebral disc, each source located in the distal portion of the probe,
wherein the first treatment source is adapted to therapeutically treat a first component of the intervertebral disc, and
the second treatment source is adapted to therapeutically treat a second different component of the intervertebral disc.
Also in accordance with the present invention, there is provided a device for therapeutically treating back pain, comprising:
a) a probe having a proximal portion and a distal portion,
b) first and second treatment sources adapted to therapeutically treat a vertebra, each source located in the distal portion of the probe,
wherein the first treatment source is adapted to therapeutically treat a first component of the vertebra, and
the second treatment source is adapted to therapeutically treat a second different component of the vertebra.
Also in accordance with the present invention, there is provided a device for therapeutically treating back pain, comprising:
a) a probe having a proximal portion and a distal portion,
b) first and second treatment sources adapted to therapeutically treat a spinal facet joint capsule, each source located in the distal portion of the probe,
wherein the first treatment source is adapted to therapeutically treat a first component of the spinal facet joint capsule, and
the second treatment source is adapted to therapeutically treat a second different component of the spinal facet joint capsule.
Also in accordance with the present invention, there is provided a method of treating back pain, comprising the step of therapeutically treating first and second components within an intervertebral disc with a single device.
Also in accordance with the present invention, there is provided a method of treating back pain, comprising the step of therapeutically treating first and second different components within a vertebra with a single device.
Also in accordance with the present invention, there is provided a method of treating back pain, comprising the step of therapeutically treating first and second different components within a spinal facet joint capsule with a single device.
In one preferred embodiment which treats different tissue sites, the inventors have recognized that back pain may be generated within an individual patient from each of the vertebral bodies which are adjacent a problematic disc. Accordingly, in one aspect of the present invention, there is provided a method of treating back pain wherein at least two separate vertebral bodies (e.g., the vertebral bodies on either side of a problematic disc) are therapeutically treated within the same procedure, preferably with a single probe.
In particular, in accordance with the present invention, there is provided a device for therapeutically treating back pain, comprising:
a) a probe having a proximal portion and a distal portion,
b) first and second treatment sources, each source located in the distal portion of the probe,
wherein the first treatment source is adapted to therapeutically treat a first vertebral body, the second treatment source is adapted to therapeutically treat a second vertebral body.
Also in accordance with the present invention, there is provided a method of treating back pain, comprising the step of therapeutically treating first and second vertebral bodies with a single device.